The invention relates to a device for shaping back of a horizontally positioned, spread out book cover which may be aligned approximately evenly distributed with a book block spine and, if applicable, may be provided on the inside with an insert. The device may consist of a shaping tool that can be moved toward the inside of the book cover back which may face the book block spine, to lift up the book cover back between two fold-forming rails that may be arranged opposite each other on the side, thereby forming a web on the back of the book cover, wherein the tool comprises two adjacent support bars extending parallel to the fold-forming rails and embodied to jointly change the distance between the bars to adjust the web width of the book cover back in a direction transverse to the longitudinal extension of the fold-forming rails.
Devices of this type are used with casing-in machines on book-production lines for shaping the back of a book cover. Following a preceding partial process during which bound book blocks are processed, in particular along the back, respectively one book cover and one book block are joined along the back in the casing-in machine before the unfinished book is compressed and folds are pressed in. The shaping of the book spine occurs while the book is conveyed along the path leading to the casing-in machine, as described and shown in German patent document DE 1,436,086 A. These steps are described in further detail on pages 466/467 and on pages 472/473 of the book entitled “INDUSTRIELLE BUCHBINDEREI” [Industrial Bookbinding] by Liebau/Heinze, 2nd Edition, ISBN 3-88013-596-7.